1. Field of the Invention
The present invention relates to a space station such as for supporting untended research experimentation in a microgravity space environment.
Outer space provides a natural microgravity and high vacuum environment which is not available on earth and which is perfect for certain research experimentation dealing with physical and chemical phenomena which are retarded, blocked, or masked by the effects of gravity.
2. State of the Art
It has been proposed to conduct such experimental research in large, manned space stations but such stations cannot provide the necessary microgravity or vacuum environment within the space station as is present in space external to the space station, due to the physical tolerance limitations of the occupants of the station. Also, manned space stations are large and complex, and they incorporate a plurality of vibration sources and excessive g-jitter which interferes with research experimentation.
Free-flying, powered space disks or platforms have been constructed and employed for ultravacuum and low gravity space experimentation. In particular, the Wake Shield and the Eureca platforms are dedicated to providing these environments to payloads. The Wake Shield Facility, is a 12-foot diameter stainless steel disk which is deployed from the cargo bay of a space shuttle and is powered and maneuvered to a location 30 or 40 miles from the shuttle and oriented to shield out the residual atmosphere that remains in low earth orbit, thereby creating an ultra-pure vacuum in its wake. This ultra-vacuum is used as an environment in which to conduct epitaxy in which exceptionally pure and atomically-ordered thin films of semiconductor compounds such as crystalline gallium arsenide can be grown in the ultra-vacuum environment which is free of contaminants.
The Eureca Free Flyer is a reusable free flying platform which, like the Wake Shield, is deployed to and retrieved from space via the space shuttle. Eureca is being made available for microgravity payloads which require a very low gravity environment and/or high vacuum. Once deployed from the shuttle bay, it is placed in an orbit in which it remains for up to a year.
Free-flying platforms such as Wake Shield and Eureca are expensive, complex and incorporate the disadvantages of vibration and g-jitter since they require power and avionics necessary to accomplish free flight and maneuverability to some distance from the orbiter, and back to the orbiter for retrieval into the cargo bay of the space shuttle for return to Earth. In addition, launch and retrieval by the Space Shuttle is very expensive and severely limits the availability of flights.
The present invention is concerned with providing a relatively inexpensive and practical solution to the problems of vibration, g-jitter and space limitations while providing an easily accessible facility for microgravity space experimentation.